Many current passenger vehicles are equipped with air bags that deploy in certain vehicle impact events. Air bag deployment usually involves relatively rapid inflation of the air bag with a gas. The inflation rate and force may be controlled in commercial passenger vehicle applications to meet various governmental regulations. Some governmental regulations relate to, for example, limiting injuries to an occupant of a child seat resulting from an air bag impacting the child seat or occupant of the child seat. Some vehicles meet such governmental regulations by providing relatively complex and expensive sensor systems that disable the air bag unless a passenger above a threshold weight is detected in a seat adjacent to the air bag.